A study led by Dr. Alexander Farnsworth from the University of Bristol suggests that humans and most other mammals could face extinction in the future due to extreme heat. This mass extinction would be linked to the formation of a supercontinent, which the research team has named "Pangea Ultima." Over millions of years, Earth’s drifting continents are expected to merge into one massive landmass, which will set off significant climate changes.

Published in Nature Geoscience, the study explains that as Pangea Ultima forms, conditions on Earth will become intensely hot and arid, making it nearly impossible for most species to survive. According to Dr. Farnsworth, three primary factors would contribute to these dangerous temperatures: the continentality effect, an increasingly intense sun, and rising atmospheric CO₂ levels. The continentality effect would mean that more of Earth’s land would be too far from oceans to benefit from their cooling influence. Meanwhile, a hotter sun will eventually emit more energy, further heating the planet. Lastly, increased volcanic activity due to tectonic shifts would release large amounts of carbon dioxide.

Dr. Farnsworth predicts that average temperatures could range from 40 to 50 degrees Celsius across much of this supercontinent, with even higher peaks and intense humidity, a lethal combination for mammals, including humans. Such conditions would make it difficult for mammals to regulate their body temperature, as sweating would no longer be effective. Food sources would also become scarce as high temperatures and dry conditions limit habitable land, with only about 8 to 16 percent of the landmass remaining viable for mammals.

While this supercontinent scenario is still some 250 million years away, researchers caution that today’s climate crisis also poses severe risks. Co-author Dr. Eunice Lo stresses the importance of focusing on today’s challenges, noting that extreme heat already endangers human health and well-being, emphasizing the urgent need to reach net-zero emissions.

Earth has experienced at least five major extinction events in its history. These include the Ordovician-Silurian Extinction (443 million years ago), which decimated marine life; the Late Devonian Extinction (360 million years ago), driven by volcanic activity and asteroid impacts; the Permian-Triassic Extinction or “The Great Dying” (252 million years ago); the Triassic-Jurassic Extinction (200 million years ago), which killed half of all species; and the well-known Cretaceous-Paleogene Extinction (66 million years ago), when an asteroid impact wiped out the dinosaurs and many other species.